Coolant Expansion Tank Pressure Test
Coolant Expansion Tank Pressure Cap Pressure TestWARNING: Never remove the coolant expansion tank cap under any circumstances while the engine is operating. Failure to follow these instructions may result in damage to the cooling system or engine and/or personal injury. To avoid having scalding hot water or steam blow out of the cooling system, use extreme care when removing the coolant expansion tank cap from a hot cooling system. Wait until the engine has cooled, then wrap a thick cloth around the coolant expansion tank cap and turn it slowly until the pressure begins to release, step back while the pressure is released from the system. When certain all the pressure has been released (still with a cloth) turn and remove the coolant expansion tank cap. Failure to follow these instructions may result in personal injury.
1. Remove the expansion tank cap from the radiator coolant expansion tank.
2. Use water to clean in area of rubber seal and vacuum relief valve. Immerse expansion tank cap in water and install expansion tank cap pressure test adapter from Pressure Tester on the expansion tank cap.
3. NOTE: If the plunger of the pump is depressed too quickly, an erroneous pressure reading will result.
Slowly depress the plunger of the pressure test pump until the pressure gauge reading stops increasing, and note highest pressure reading obtained.
4. Release pressure by turning the pressure relief screw counterclockwise. Then tighten the pressure relief screw and repeat Step 5 at least twice to make sure the pressure test reading is repeatable and within acceptable gauge reading limits of the expansion tank cap.
5. If the pressure test gauge readings are not within acceptable gauge reading limits, install a new expansion tank cap.